Interplay of Halogen and Hydrogen Bonding through Co-Crystallization in Pharmacologically Active Dihydropyrimidines: Insights from Crystal Structure and Energy Framework.

A solvent-assisted grinding method has been used to prepare co-crystals in substituted dihydropyrimidines (DHPM) that constitutes pharmacologically active compounds. These were characterized using FT-IR, PXRD, and single-crystal X-ray diffraction. In order to explore the possibility of formation of halogen (XB) and hydrogen bonding (HB) synthons in the solid state, co-crystallization attempts of differently substituted DHPM molecules, containing nitro, hydoxy, and chloro substituents, with different co-formers, such as 1,4-diiodo tetrafluorobenzene (1,4 DITFB) and 3-nitrobenzoic acid (3 NBA) were performed.

Antidiabetic Activity of Dihydropyrimidine Scaffolds and Structural Insight by Single Crystal X-ray Studies.

Background: This research project is designed to identify the anti-diabetic effects of the newly synthesized compounds to conclude the perspective of consuming one or more of these new synthetic compounds for diabetes management.

Introduction: A series of dihydropyrimidine (DHPM) derivative bearing electron releasing and electron-withdrawing substituent's on phenyl ring (a-j) were synthesized and screened for antihyperglycemic( anti-diabetic) activity on streptozotocin (STZ) induced diabetic rat model. The newly synthesized compounds were characterized by using FT-IR, melting point, 1H and 13C NMR analysis.

Crystal structure of a 1:1 cocrystal of nicotinamide with 2-chloro-5-nitro-benzoic acid.

In the title 1:1 cocrystal, CHClNO·CHNO, nicotinamide (NIC) and 2-chloro-5-nitro-benzoic acid (CNBA) cocrystallize with one mol-ecule each of NIC and CNBA in the asymmetric unit. In this structure, CNBA and NIC form hydrogen bonds through O-H⋯N, N-H⋯O and C-H⋯O inter-actions along with N-H⋯O dimer hydrogen bonds of NIC. Further additional weak π-π inter-actions stabilize the mol-ecular assembly of this cocrystal.

Crystal structure and Hirshfeld surface analysis of diethyl 2-[4-(4-fluoro-phen-yl)-2-methyl-4-oxobutan-2-yl]malonate.

The title compound, CHFO, was synthesized by reacting diethyl malonate with 1-(4-fluoro-phen-yl)-3-methyl-but-2-en-1-one. The mol-ecule adopts a loose conformation stabilized by weak C-H⋯O and C-H⋯π inter-actions. In the crystal, the mol-ecules are joined by C-H⋯O contacts into infinite chains along the axis direction with a (6) graph-set motif.

Structural analysis of 2-iodo-benzamide and 2-iodo--phenyl-benzamide.

The title compounds, 2-iodo-benzamide, CHINO (I), and 2-iodo--phenyl-benzamide, CHINO (II), were both synthesized from 2-iodo-benzoic acid. In the crystal structure of (I), N-H⋯O and hydrogen bonds form two sets of closed rings, generating dimers and tetra-mers. These combine with C-I⋯π(ring) halogen bonds to form sheets of mol-ecules in the plane.

Crystal structure of 1-[3,5-bis-(tri-fluoro-meth-yl)phen-yl]-2-bromo-ethan-1-one.

The title compound, CHBrFO, synthesized continuous stirring of 3,5-bis-(tri-fluoro-meth-yl) aceto-phenone with bromine in an acidic medium and concentrated under reduced pressure, crystallizes with four mol-ecules in the unit cell ( = 4) and one formula unit in the asymmetric unit. In the crystal, mol-ecules are linked in a head-to-tail fashion into dimers along the axis direction through weak C-H⋯Br and C-O⋯C inter-actions. C-H⋯O, C-F⋯π and F⋯F inter-actions are also observed.

Larvicidal study of tetrahydropyrimidine scaffolds against Anopheles arabiensis and structural insight by single crystal X-ray studies.

A series of methyl or ethyl 4-(substitutedphenyl/pyridyl)-6-methyl-2-oxo/thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate (HPM) analogues 4a-g were synthesized and evaluated for larvicidal activity against Anopheles arabiensis. These newly synthesized compounds were characterized by spectral studies such as FT-IR, NMR ( H and C), LC-MS, and elemental analysis. The conformational features and supramolecular assembly of molecules 4a, 4b, and 4e were further analyzed from single crystal X-ray study.

Crystal structure of methyl 4-(4-hy-droxy-phen-yl)-6-methyl-2-oxo-1,2,3,4-tetra-hydro-pyrimidine-5-carboxyl-ate monohydrate.

The title hydrate, CHNO·HO, crystallizes with two formula units in the asymmetric unit (' = 2). The dihedral angles between the planes of the tetra-hydro-pyrimidine ring and the 4-hy-droxy-phenyl ring and ester group are 86.78 (4) and 6.